How To Build A Grow Room In A Garage?

A garage is a great place to build a grow room because it is often a blank slate. When you set out to build a grow room in your garage, you can essentially start from scratch protecting the floor, insulating effectively and adding just the right level of heating, cooling, ventilation and lighting to nurture your plants. In this article, we provide smart tips to help you set up a grow room in your garage. Read on to learn more.

What Is A Grow Room?

What Is A Grow Room

A grow room is a completely self contained interior room set up to grow plants. It is sealed from outside influences and equipped with good ventilation and ample artificial light.

Grow rooms are very popular among marijuana growers, and they can also be used to grow a wide variety of edible and ornamental plants.

What’s The Best Size Grow Room?

There is really no set “best size”. You can set up a grow room in a closet, in your basement, in a room in your house or in an outbuilding or garage. Choose the size that best suits your needs.

How Is A Grow Room Different From A Greenhouse?

Greenhouses make use of the natural elements. A greenhouse depends a great deal upon the sun for light and warmth. Most greenhouses have windows and doors that open to the outside for ventilation.

A grow room (typically) is entirely self-contained. A greenhouse is to a grow room as an outdoor pond is to an aquarium.

Why Is It Good To Grow Plants In A Grow Room?

When you keep your plants in a grow room, you are in complete control of every element of growing, such as:

  • Temperature,
  • Humidity
  • Light
  • Pests

These carefully controlled elements work together to keep your plants healthier. This benefit’s the health and vigor of your plants, and if you are selling your crop, it brings you a greater return on investment.

This video shows the construction of a grow room in an interior room, but this process could easily be adapted for use in a garage.

What Steps Should You Take To Set Up A Grow Room In Your Garage?

1. Choose your space

Do you want to convert your entire garage into a grow room, or do you want to create a room within a room situation that partitions off part of your garage?

Be sure to keep the essential needs; warmth, light, ventilation, water and drainage in mind as you select your space.

2. Make a plan

Don’t just wing it or make it up as you go along. Once you have identified the space you want to use, take some time to plan how and where you will place your ventilation, heating and cooling elements, lighting, water source and drainage system.

Map out exactly how and where you will place your plants.

3. Create a comprehensive list

Before you take any steps to set up your grow room, you must think about what sort of materials you have on hand (or need to purchase). Make a list of all the elements you will need to purchase, such as:

  • Wall and ceiling materials
  • Shelving for plants
  • Storage cabinets
  • Air conditioning
  • Exhaust fans
  • Insulation
  • Plumbing
  • Lighting
  • Heaters
  • Flooring
  • Wiring
  • Vents

A detailed, itemized list will help you prepare efficiently. It will save you time and money and will prevent unwanted and unpleasant surprises throughout the process.

4. Take care of your wiring

If your garage does not have ample electrical wiring and outlets, you should take care of this first thing. In a damp setting, you do not want to have electrical lines, extension cords and power bars littering up the place.

Install correct electrical wiring to suit your needs before installing wall and ceiling panels. If you are not able to do it yourself, hire a pro. This is important.

5. Insulate the walls and ceilings

If your garage walls and ceilings are already finished with sheetrock or wood, you may need to remove that material and replace it with a more moisture resistant material or treat or cover it to prevent damage that could be caused by high levels of humidity.

Reflective aluminum bubble wrap insulation is a very good choice for a grow room. It’s extremely easy to work with, insulates well, provides the sort of reflective properties you’ll find in Mylar and is both water resistant and breathable.

It can easily be installed over windows to provide privacy and protection against variable exterior temperatures.

If you already have another sort of insulation in place, you may just want to line your walls and ceilings with lightweight Mylar, but reflective aluminum bubble wrap insulation is really a smarter, more durable choice, and extra insulation is always a good thing.

Another option with good reflective properties for a space that is already insulated and has finished walls is flat white paint.

While it is not quite as reflective as Mylar or aluminum insulation, it does provide quite a bit of boost (as much as 85%) for your lighting system.

6. Attend to the flooring

A sealed cement garage floor can be adequate for a grow room (especially if it has drainage in place) but if you are working with a gravel or dirt floor, you’ll need to seal it and cant it to allow for water runoff.

Getting a good floor in place is similar to laying a good foundation. Sealed cement can be a good floor for a plant room, but if you don’t have cement floor in your garage, materials such as pond liner or rubber flooring can help prevent humidity and runoff damage.

7. Install your lights

Of course, lighting is extremely important in a grow room. A grow light system controlled by timers is ideal.

Although the classic grow room is self-contained, if your garage has windows or skylights that allow a significant amount of natural light, this can be very helpful in maintaining healthy plants and saving on expenses.

Once you have your walls and ceilings insulated and your flooring in place, you can set up your lighting system.

Generally speaking, a good grow room needs 600 watts of light every five or six feet. Remember that your light will also provide heat, so you’ll need to set up your ventilation system accordingly.

The amount of light and heat provided by different sorts of artificial light sources varies. Your choices in artificial lighting include:

  • LED
  • Fluorescent
  • Incandescent
  • High Pressure Sodium

The classic grow room relies entirely on artificial light, but if you have well insulated windows that provide good light, you may want to make use of the light of the sun and supplement it with artificial light.

To determine how much lighting you’ll need, you must evaluate the amount and quality of natural light available and take into consideration the amount of light your plants need.

8. Install your ventilation system

Good ventilation, in the form of vents and exhaust fans, is also a prime concern in a grow room. Poor ventilation leads to many different sorts of mold related plant maladies.

Measure the square, cubic footage of the space to determine the size and strength of the ventilation system.

You will need a system that brings in fresh air and expels hot, stale air. Fresh air should come in at floor level, while hot, used air should be expelled near the ceiling. This mimics the natural flow of air.

It’s a good idea to direct the flow of air over your lighting source to help disperse collected heat and prevent hot spots.

Horizontal air flow fans (standard table fans or floor fans) directed into the corners of the room will keep the air moving and help prevent excessive humidity and condensation.

As a general rule of thumb, you’ll want to set up your ventilation system so that it has double the capacity or wattage of the lighting system you will be using.

The reason for this is that, in addition to controlling humidity, your ventilation system keeps the heat from your lights circulating and prevents heat buildup and hot spots. Still air and focused heat can lead to burned plants.

9. Set up your watering system

In a climate controlled room such as a grow room, plants actually dry out pretty quickly. It’s smart to set up an automated watering system to keep up with your plants’ hydration needs, even in your absence.

You’ll also need to set up a sink that allows you to attend to your plants as needed. Laundry room sinks are inexpensive, easy to install and provide a good, deep tub for cleaning containers and equipment and giving plants a good soak.

10. Consider hydroponic plant culture

Many grow room gardeners use a hydroponic system to keep their plants thoroughly hydrated and deliver valuable nutrients on a regular basis.

Growing plants hydroponically eliminates the need for planting soil, and removes problems associated with hauling and storing potting medium and the mess involved in potting, repotting or even simply walking in and out of the grow room.

Some growers combine hydroponics with use of a sterile, nutrient free growing medium such as coco coir. This can be helpful with plant root development.

Still others simply use potting soil or homemade compost. This is by far the least expensive substrate option, even if it is a bit messy.

11. Install shelves and containers and any peripheral equipment you have in mind

Before you add any plants, be sure to have a place for them to go and all your odds and ends in place, such as pH meter, humidity meter, thermometer, etc. in place.

It’s best to start out with your grow room structure established before you ever attempt to grow anything.

Get planting! With all of your groundwork laid, it’s time to plant seeds and/or seedlings and add any sort of vegetation you have in mind!

Happy Growing! And if you would like to use your newly grown plants, here is our guide to building a commercial kitchen.

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